Changeable centrifugal pump



1921. 2 SHEETS-SHEET l.

|. KUROISHI.

CHANGEABLE CENTHIFUGAL PUMP.

APPLICATION FILED IUNE 3 1918. 1,374,747. Patented Apr. 12

I. KUROISHI.

GHANGEABLE cENTmFuGAL PUMP.

APPLICATION FILED JUNE 3. l1.918.

Patented Apr. 12, 1921.

2 SHEETS-SHEET 2- UNITED' STATES ICHIJ'I KUROISHI, 0F TOKYO, JAPAN.

CHANGEABLE CENTRIFUGAL PUMP.

Specification of Letters Patent.

Patented Api'. 12, 1921.

Application led .Tune 3, 1918. Serial No. 237,991.

To all lwhom it may concern:

Be it known that I, ICHJJI KURoisHI, a subject of the Emperor of Japan, and residing in Tokyo, Japan, have invented certain new and useful Improvements -in Changeable Centrifugal Pumps, of which the following is a specification.

This invention relates to a turbine pump in which a slidable or rotatable guiding ring is provided opposite to a fixe guide disk between a pair-of impellers to constitute a water passage between the guiding elements, and by shifting or adjusting the rotatable ring to change the positions of the slots therein, water is either caused to pass through a two step passage of successive sets of rotating vanes, or topass through only one assage in each set of the vanes by divide ly flowing into them simultaneously. Further, high or low pressure water in each side of the pump is put in communication by means of a small tube, which is provided in its midway with a three way cock. The parts constituting each step of the water passage are made to slide along the axis of the pump and the end chamber for one passage is made somewhat larger than that for the other. Therefore, when high pressure water is introduced into a space between the larger end chambers and the casing wall of thepump, the fixed guiding disk in each step of the water passage is pressed against the rotatable guiding ring. On the other hand when low pressurewater .is introduced therebetween, the vanes are separated and released.

The invention further includes a modiication in which the positions of the exhaust-port, the suction port and the 'check valve are the same as above described. But, in which, instead of using the said valve or cock, the water passage in the pump casing and opposite to the guiding slot of the impeller is separated into two different systems, one of which is extended to the exhaust port opposite to the said guiding ring and the other is communicated with the inlet port of the next impeller. Accordingly to cause the guiding slot of the guiding ring to be communicated with one or the other of the said separated oi' divided water passage, the pump will work as a series impeller or a parallel impeller. l

The object of the invention is to obtain by merely changing the direction of water is therefore very suitable foi` travel, a pump which may work under continuous efhcieiicy enabling the lift and delivery of water pump to be freely changeable without varying number of rotation, horse power and efficiency, etc. The pump changeable pumps such as fire pumps or sinking pumps, etc. A further object of the invention is to obtain a changeable centrifugal pump which will eliminate the inconvenience of arranging a large number of independent and different types of pumps such as require the variation of lift, for instance, fire pumps or sinking p umps, as well as ordinary pumps for working under varying lifts, and thereby satisfy the many demands for the variation of lifts with only one pump. The second modification thereof is very suitable for the pumping out of well water, while the first modification is especially adapted for small fans.

Referring to the accompanying drawings which show examples of the pump according to this invention, and wherein similar characters of reference are employed to indicate corresponding parts; Figure 1 is a longitudinal central section thereof showing the application of this invention to a series impeller type; Fig. 2 shows detail views tof the main improved parts of this invention; Fig. 3 is a sectional view taken in line 3 3 of Fig. 1 and shows a device for sliding one of the guiding vanes; Fig. 4 is a .sectional elevation of a modification of the improved pump and shows another series impellervtype. Fig. 5 is a sectional view taken in line 5-5 in Fig. 4.

The invention may of course be applie to pumps having more than two sets of iinpellers, but as the above type, viz., havin two sets of impellers is represented, the following description will be given to this type of the centrifugal pump.

In Fig. 1, l represents fixed guiding elements in the form of disks having hub ortions and outer annular portions: provided with slots and 2 the rotatable or slidable tobe combined with l and 2. One or the other manner of combination of these parts constitutes a passage for either two steps of total lift, or a passage for one step of half lift and double delivery. The parts may of course be designed to constitute any number of steps for the required lift and delivery in the same manner.

A screw shaft 5 is geared with a segmental worm wheel to control the variation of the water passage in 2. Fig. 3 is a detail view of this .part and the handle 6 of the screw shaft may be worked by hand or, if necessary, by some automatic means, (not shown) so that ring 2 is slidably rotated to some eX- tent. A small by-pass tube 7 is provided with a three way cock 8, by means of which suction pressure water is transmitted through small ports 9 and 10. Thus the high pressure in'the water passage 11 relieves the contacting surfaces 12 and water passage 13, these parts all being arranged to be slidable in longitudinal direction within the pump casing 14. 0r high pressure water may be introduced through ports 15 and 9 and thus cause the parts 12 and 13 to be contacted together.

Now, assuming that when the above described pump is working under a certain velocity with a totalI lift and a corresponding delivery, then the guiding slot 16 of the slidable guiding rin 2 is in alinement with the water passage 17 of the fixed guiding element 1. Thus, the side wall of the element 1 constitutes a right angular water passage together with the peripheral wall of the guiding vane 2. Therefore the water ejected through the impeller 4 of the first step makes one travel in the guiding slot and then enters into element 1 through Water passage 17 and the impeller 3 of the second step to make the second travel, and thus completes the total pass in the same manner (see Figs. 1 and 2). In this case, the water passage from the suction 20 to the exhaust 21 is shown by chain line, and its direction is indicated by arrows (see Fig. 1).

When it is desired to change the lift and delivery of the pump worln'ng under the above described conditions, the ports 9 and 10 are arranged in communication with each other by means of the cock 8 and this releases the contact of the contacting surfaces 12 of each set of the elements. Then the handle 6, which is of course arranged in an alternative step from the first step of the vane, is rotated to slide the respective slid-- able ring 2 until slot 22 alines or registers with slot 16 and slot 17 with slot 24. 'in this position, the guiding slot 16 is encircled by the side wall 25 and the intermediate wall 26 of the guiding elements (Fig. 2), the one side of the outlet 27 of the disk element only being opened. Therefore, after passing through a course the same as the first step as above described, the water comes out directly from the outlet 27 and enters the passage 13. The water passages 17 and 24 and the second impeller 3 are all in com-v suitably chosen, the second described working of the improved pump gives a half lift of double delivery under the same working power. This is clear because the horse-power required WHP is equal to CQH, where Q is quantity of water lifted, H the lift and C a certain constant.

When the above two modes of operation of the improved pump are suitably arranged, the pump may be worked in any desired lift and any desired corresponding delivery under practically the same efficiency. In these cases, the passage of water from the suction 20 to the exhaust 21 is indicated by full line and the direction thereof is shown by arrows (see Fig. 1).

In Figs. 4 and 5, 42 and 43 represent the impellers; 44 and 45 the outer casings; 46 the casing cover having the suction branch tube, and 47 the suction main. A fixed guiding element 48 is now employed while 49. represents a slidable guiding ring, each guiding slot of which is provided with a toothed segment opposite to the divided water passage. This toothed segment is geared with a toothed wheel 50. 51 designates the rotating shaft; 52 the check valve and 53 the handle. The parts 36, 37, 34 and 35 and the exhaust and suction tubes are here illustrated in their simplest, forms to make clear their explanation. Therefore any other modifications of shape or type thereof which will achieve the purpose -of this invention, does not depart from the scope of this invention.

When the invention is applied to a series impeller pump as sho-wn in Figs. 4 and 5 the wheel is rotated until the guiding slot 69 of the part 49 registers with water passage 70 in casing 45. Then the part 52 is automatically opened and assumes the position shown in chain line. Therefore water will be divided from 71 into 72, 73, 74 and 75 and reaches to v76, 77, 78 and 79. It will thus be seen that the pump will act as one step type, and the delivery of the pump in this case is doubled.

Also when the slot of the part 49 is adjusted to a position opposite to the water passage 81 in 45, then the water passage 82 in the part 45 is shut by the outer wall 83 of the part 49 and the part 52 is, as shown in full line, automatically shut by the water pressure in 74. Therefore water will pass from 71 through 72, 73, 74, 75 and 78 to 79, the pump becoming its normal state of series impeller type as shown in Fig. 4.

As above described, the number of series in parallel.

of impeller ,may be increased as desired. Moreover, the pump may be applied to fans. In this case there is no necessity to change or modify the construction thereof and therefore no further explanation is required.l

Having thus fully described the invention What is claimed is new and desired to be securedby Letters Patent is 1. A changeable centrifugal pump consisting of an outer casing, an inlet leading to thev casing, an outlet leading from the casing, inner casings formed in the outer casing, a shaft extending through the casings, passages provided in the outer casing for arranging the inner casings in' connection with each other, impellers mounted on the shaft, and coacting stationary disks and shiftable elements mounted in the inner casing and provided With openings for registration With each other and for registration with the passages and the impellers, and manually controlled means in the inner casing for placing the impellers in series or 2. A device as set` forth in claim 1 wherein the shiftable elements are provided with rack portions on their periphery, and Wherein the manually controlled means consists of rotatable stub shafts, coi; on the stub shafts meshing with the rac portions and manually operable means for facilitating the rotation of the shafts so as to place the impellers in series or in parallel.

3. A changeable centrifugal pump consisting of an outer casing, an inlet leading to the casing, an outlet leading from the casing, inner casings arranged in the outer casing, disk: guiding elements arrangedin the inner casing forming partitions, a shaft extending through said casing and elements being provided in the outer casing for arranging the inner casings in connection with each other, impeller vanes mounted on the shaft arranged Within the inner casing on opposite sides of the guiding elements, a shiftable ring mounted in proximity to each stationary guiding element, th'e disk elements and rings being provided with openings registerable with each other and with the passages for controlling the iow of Water and manualy controlled means in the inner casings for adjusting the shiftable rings so as to place the impeller vanes in series or in parallel.

In testimony whereof I have hereunto set my hand in presence of two subscribing Witnesses.

ICHIJI KURoIsHI. [a 5.] 

